Memory metal activation system

Abstract

A memory metal expands through the use of a catalyst and a fuel-oxidizer mixture. The catalyst can be placed directly onto the surface of the memory metal, or it can just be in the proximity of the metal. The fuel-oxidizer mixture similarly can be placed on the surface of the metal or just near the metal. The oxidation of the fuel can be initiated by a spark, heat, or some other source, and the heat from the exothermic reaction raises the temperature of and causes the expansion of the memory metal.

1. A system comprising:
 a memory metal; and 
 a catalyst, wherein said catalyst is disposed as a coating on a first surface of said memory metal. 
 
     
     
       2. The system of  claim 1 , further comprising a fuel-oxidizer mixture. 
     
     
       3. The system of  claim 2  wherein said fuel-oxidizer mixture is disposed on said first surface of said memory metal. 
     
     
       4. The system of  claim 2  wherein said fuel-oxidizer mixture is disposed on a second surface of said memory metal. 
     
     
       5. The system of  claim 2  further comprising a reaction initiator to commence a reaction of said fuel-oxidizer mixture. 
     
     
       6. The system of  claim 2  wherein said fuel-oxidizer mixture is selected from the group consisting of hydrogen-oxygen, ammonia-oxygen, hydrocarbon vapor-oxygen, and alcohol vapor-oxygen. 
     
     
       7. The system of  claim 2  wherein said fuel-oxidizer mixture comprises a monopropellant. 
     
     
       8. The system of  claim 1  further comprising a heat source, wherein said heat source provides a sufficient amount of heat to said system to provide a self-sustaining reaction. 
     
     
       9. The system of  claim 1  wherein said memory metal comprises NITINOL. 
     
     
       10. The system of  claim 1  wherein said memory metal comprises a tube. 
     
     
       11. The system of  claim 1  wherein said memory metal comprises a wire. 
     
     
       12. The system of  claim 1  wherein said memory metal comprises a plate. 
     
     
       13. The system of  claim 1  wherein said catalyst is selected from the group consisting of palladium, platinum, and copper. 
     
     
       14. A system comprising:
 a memory metal; and 
 a fuel-oxidizer mixture, wherein said fuel-oxidizer mixture is disposed as a coating on a first surface of said memory metal. 
 
     
     
       15. The system of  claim 14 , further comprising a catalyst. 
     
     
       16. The system of  claim 15  wherein said catalyst is disposed on said first surface of said memory metal. 
     
     
       17. The system of  claim 15  wherein said catayst is disposed on a second surface of said memory metal. 
     
     
       18. The system of  claim 14  further comprising a reaction initiator to commence a reaction of said fuel-oxidizer mixture. 
     
     
       19. The system of  claim 14  further comprising a heat source, wherein said heat source provides a sufficient amount of heat to said system to provide a self-sustaining reaction. 
     
     
       20. A method comprising:
 providing a memory metal having a catalyst disposed as a coating thereon; and 
 exposing said memory metal and said catalyst to a fuel-oxidizer mixture. 
 
     
     
       21. The method of  claim 20  further comprising initiating a reaction of said fuel-oxidizer pair using a reaction initiator. 
     
     
       22. The method of  claim 20  wherein the operation of exposing further comprises flowing said fuel-oxidizer mixture over said memory metal and said catalyst. 
     
     
       23. The method of  claim 20  wherein the operation of exposing further comprises applying said fuel-oxidizer mixture to said memory metal. 
     
     
       24. The method of  claim 20  wherein selection of at least one of: (1) choice of catalyst; (2) amount of catalyst; (3) choice of fuel-oxidizer; and (4) amount of fuel-oxidizer results in a non-sustaining reaction. 
     
     
       25. The method of  claim 24  further comprising applying heat so that said reaction is sustained. 
     
     
       26. The method of  claim 25  further comprising controlling said amount of fuel-oxidizer mixture so that a sum of heat applied and heat generated during said reaction balances loss of heat. 
     
     
       27. The method of  claim 20  wherein a reaction of said fuel-oxidizer mixture occurs in a transition temperature range of said memory metal. 
     
     
       28. The method of  claim 20  further comprising flowing air over said memory metal. 
     
     
       29. The method of  claim 28  further comprising ceasing exposure of said memory metal and said catalyst to said fuel-oxidizer mixture.